Pressure-regulator for automatic brakes.



J. E. A. MICHEL.

PRESSURE REGULATOR FOR AUTOMATIC BRAKES,

APPLICATION FILED APR.6,19OB.

iiatenified eps. 27, 1 .910.

3 SHBBTS SHBET 1.

E. A MICHEL.

PRESSURE REGULATOR FOR AUTOMATIC BRAKE.

APPLIOATIOH FILED 11212.6, 1908.

3SHEETSSHEET 2.

Mgr

J. E. A. MIGHEL. PRESSURE REGULATOR FOR AUTOMATIC BRAKES. APPLIOATION FILED APR.6,1908.

la'aiente Sept. 2?, 1910.

3 SHEETS-SHEET 3,

France, have invented a Pressure-Regulator for Automatic Brakes, of which the following is a specification.

' arrangement of the diaphragms and the man JOSEPH EDOUARD ALEXANDRE MICHEL, OF PARIS, FRANCE.

PRESSURE-REGULATOR FOR AUTOMATIC BRAKES.

Application filed April '6, 1

Specification of Letters Patent. P tented Sept. 2'7, 1910.

90s. I Serial No. 425,479.

To all whom it may concern:

Be it known I, J osnrn Enommo ALnx- ANDRE MICHEL, a citizen of the Republic of France, and resident of 15 Rue Clavel, Paris,

he present invention relates to a system of pressure regulators more s ecially applicable to automatic air-bralies. These pressure regulators may be employed either as an engineers valve or as a distributing valve for the brake cylinder according to the ner in which they are controlled.

Figure 1 is a diagrammatic illustration of an apparatus as employed 'as an engineers valve. Fig. 2 is a vertical sectionalview of a modified form of the invention. Fig. 3 is a vertical sectional view on line w-y of Fig. 2, Fig. 4 is a sectional view'partly in elevation of details seen in Figs. 2 and 3. Fig. 5 is a plan view showing certain details, some of the latter, being in section. Figs. 6 and? are vertical sectional views of further modified forms of the invention. Fig. 8 is a sectional elevation of the non-return valves. Figs. 9 and 10 are vertical. sectional views showing modified arrangements of the diaphragms. Fig. 11 is a vertical sectional view of a further modified form of the invention.

A is a chamber communicating with the train pipe B, at C with the air reservoir and at D with the atmosphere through the medium of two valves E and F respectively, the former of which opens from the chamber A into the reservoir G and the latter F from the atmosphere into the chamber A. The two valves E, F are joined to a. lever G attached by means of a rod H to a diaphragm I, which forms a part of the side of the chamber A and which consequently is subjected on one of its faces to the pressure prevailing in that chamber and on the other to'atmospheric pressure. This diaphragm I is moreover exposed on the outside to the action of a spring J the tension of which maybe modified as desired by means of a lever K guided on a sector L.

The action is as follows: Let P be the pressure of the reservoir C, and p the pres sure to be admitted into the train pipe. Supposing that at the beginning the pressure in the train pipe is nil and it be desired to create the pressure p, the spring J which forces back the diaphragm I with the rod H and the lever G is compressed by the lever K, the result of which is that the valve E opens, the valve F remainingclosed. Consequently, the air in the reservoir C enters the chamber A and the train pipe until the pressure on the diaphragm I balances the action of the spring J, at which moment the valve E closes. If the pressure 7) thus established in the train pipe and the chamber A becomes reduced, the spring J which is kept under uniform tension the lever K being placed at the necessary point, becomes preponderant again and causes the valve E to open once more, which brings the pressure in the train pipe to that which is desired and is determined by the position given to the lever K which regulates the pressure of the spring. If it be supposed now that in order to effect braking 1t;be desired to reduce the pressure in the train pipe or in factto get rid of it entirely, the lever K is operated so as to reduce the tension of the spring J, the result being that the pressure of the compressed air on the diaphragm I becoming preponderant, forces the latter outward, which enables the valve E to close and causes the valve F to open, thus putting the chamber A and the train pipe in communication with the atmosphere.

The apparatus shown in Figs. 2 to 4 differs from the preceding apparatus inasmuch as it has two diaphragms I and I the surfaces of which differ. The air that enters A acts as previously, but in consequence of the difference in the action on the two surfaces, its pressure can be balanced by a less powerful spring J, while diaphragms I and I with large surfaces can be employed giving the rod H a sufficient course for operating the valves E and F. The spring J may be replaced by two springs J J Fig. 3. Under these conditions, the variations of pressure, in the train pipe are effected by actuating the spring J which in the example illustrated appears as a drawspring with suitable limits of tension and J has a fixed tension. A device of any suitable construction, such as a cam or eccentric, operated by a handle T is adapted to act upon a rectangular lever U pivoting at I in order to influence more or less the spring J which by means of lever V pivoting at P exerts upon the diaphragm I the additional pressure desired. This way of operating is justified in connection w th automatic brakes by the fact that a partial reduction is suflicient for obtaining the maximum brake effect. In order to take off the brake as quickly as possible, as large as possible a communication must be established between the principal brake reservoir and the train pipe while the engine-driver is operating the valve. As soon as the brake has been taken off and the driver releases his handle, it is necessary that there should no longer be any communication between the train pipe and the principal reservoir except through a very narrow opemng, 1n order not to interfere with an emergency braking caused for example through the opening ofan auxiliary valve in one of the carriages. This object is attained by the rod H lodging in its upward course against the cam or a part dependent thereon so as to open the valve E but very slightly, just sufficient for compensating the slight leakages which areunavoidable in any system of pipes. On the contrary during the braking the engine-driver presses on the handle T, so that the plane of the cam rotates around the horizontal axis passing through thus enabling the rod H to rise higher, which causes the valve E to open still wider. In practice, the handle has a pawl X which engages with a toothed sector. In order to operate the brake it is necessary to press downthe handle for the purpose of releasing the pawl; the handle is put in the required position and when once released is retained by the pawl X engaging in the proper tooth of the rack.

Figs. 4 and 5 show the handle, cam, pivot and rack. The rectangular lever U which actuates the spring with variable tension can be provided with a handle Z which permits the increase of the total pressure of the general conduit beyond the normal limit, with the object of producing in this conduit a momentary excess of pressure in case of difficulty of releasing.

If it be desired to apply this valve to direct brakes, it is no longer possible to act on the diaphragm I through twosprings, one of which is of uniform tension and the other of variable tension, for the pressure in the pipe of the train must be varied from zero to the maximum allowed. Consequently, the tension transmitted to the diaphragm I must vary from zero to a maximum. The spring J is disposed with or it is replaced by a weak draw spring for the purpose of easily effecting a complete evacuation of the train pipe, the total regulating action being produced. entirely by the draw spring J In this case, the operating cam must be put inversely that is to say the extreme left hand position of the handle must correspond to a pressure of nil in the train pipe, this for the purpose of conforming to a generally accepted practice. Thus with a slight modification this valve could be applied also to the vacuum brake. necessary is to reverse the action of the valves and of the spring J For this latter purpose for instance, the fixed pivot P of the lever V is placed between the point where the spring J acts and the point of connection with the diaphragm, so as to cause a lowering of the latter.

The valves may be operated as shown in Fig. 1, or as shown in Fig. 2. In the latter figure, the rod H operates two lovers G G, which pivot around two fixed points 0 0. These two levers actuate the valves E and F in the proper direction. The device is arranged in such a manner that durin the mounting of the apparatus the rod is able to turn on its axis without having any influence on the operation. In a general manner likewise the mechanical arrangements for operating the two valves through the upward movement of the rod H may be carried out with various modifications originating in ordinary mechanics.

By what is stated above it will be seen that a pressure regulator is created by the arrangement of one or two diaphragms controlling a rod H which operates an inlet valve or an exhaust valve according to the direct-ion in which it is moved, the air admitted into the chamber A acting on the diaphragm or diaphragms so as to overcome the force acting on the rodH.

Suitably arranged this apparatus can be employed as a distributor for the brake cylinder. In this case, the pipe C (Fig. 6 communicates with the reservoir in whic the air is stored and the ipe M communicated with the brake cy inder. Moreover the impulsion imparted to the rod H is effected from a distance by means of variations of pressure produced in the train pipe.

All that is For this purpose it is only necessary to impart to the adjustable spring J 2 tension so as to equilibrate the action of the air from the train-pipe above the diaphragm I, when this pressure is the maximum pressure allowed or the normal working. The tens1on of the spring may even be sli htly less in order that during the removaI of the brake the valve F which establishes communication between the chamber A and the atmosphere through the pipe D may be slightly open.

The operation of the valves E and F which have respectively the function of admitting air from the reservoir C to the pressure corresponding to brake cylinder and of placing the latter in communication with the atmosphere, is effected by the difference of pressure under the diaphragm I, through the spring J and on the diaphragm I through the pressure of the train plpe which is modified as may be desired by means of the drivers valve, of the type described above or any other type. In this case it should be observed that the regulation of the pressure in, the chamber A which in the preceding apparatus results from the variation of the spring J or from the tension of the springs J and J, is due to the difference between the actions of the spring J on the diaphragm I fixed once for all and the antagonistic pressure of the train pipe on the diaphragm T on the one hand and the varlations of pressure on the internal suring off at faces of these two diaphragms on the other hand.

It is. of course understood that the auxiliary reservoir is fed by the train pipe with an intermediate non-return valve.

Fig. 7 illustrates a modification of Fig. 6. The'action of the spring J 2 is replaced by theaction below the diaphragm I of the compressed air stored in a reservoir in communication through the pipe N which maintains a constant pressure below this diaphragm. As this is necessarily the maximum pressure allowed in the train pipe, it is not possible to cause the air to act directly from this on 1 for I and I having different diameters, there would no longer be the necessary equilibration at the moment of the maximum of pressure in the train pipe. Consequently, an auxiliary diaphragm J is employed with a diameter equal to or rather slightly larger than that of T in order, as has been explained, to effect a complete and rapid removal of the brake, without excess pressure in the train-pipe, that is, without being forced at the moment of releasing to admit into the train-pipe a pressure in excess of the normal maximum pressure, and under these circumstances the two diaphragms J and 1 are separated by asmall chamber in communication with the atmosphere. In order to insure constant pressure on the dia hragm T the reservoir branch- Ei (which we will call the regulating reservoir) is connected with the train pipe through a non-return valve. At the moment when the maximum pressure is introduced in the train pipe, the regulating reservoir is filled at this pressure and when the pressure is lowered, thisrpressure will remain the same during the whole braking period, in consequence of the action of the non-return valve. This non-return valve must be similar to that illustrated in Fig. 8 without a spring and arranged so that its weight keeps it open; its stroke is limited by a pin a. Under the valve arrangement described, the weight of the valve oflers resistance to the closing of the valve for slow depressions. The opening of the valve and its weight are regulated so that with a.more sudden reduction the valve closes and the braking period is commenced. The valve can also be arranged so that its weight closes instead of opening it. In this case all that is required for effecting the same operations is to furnish the valve with a weak spring which keeps it open and to regulate the opening of the valve in a suitable manner. This is in fact the course that may be followed if it be desired to e1imi-' nate the action of the weight of the valve. This would then be as light as possiblein order to have as small as possible a mass.

Valves acting under these conditions have already been employed in certain ways but not for the purpose under consideration here.

Instead of causing the regulating reservoir to communicate with the main conduit, it may be made to communicate with the auxiliary reservoir as illustrated in Fig. 7. The non-return valve 11 which establishes communication between the auxiliary reservoir and the regulating reservoir is of the kind previously mentioned, likewise the non-return valve 6 between the train pipe anclthe auxiliary reservoir. At the moment when the pressure is at the maximum in the train pipe, the auxiliary reservoir and the regulating reservoir will be put successively in equilibrium of pressure Finally,-the valve 6 may be dispensed with, and in this case the regulating reservoir branching off at N is omitted. It cannot be said that the pressure remains uniform on the diaphragm I during the whole braking period, for, in consequence of the expansion of the auxiliary reservoir into the brake cylinder the pressure is less reduced in proportion as the volume of the auxiliary reservoir with the cylinder is larger. Under the conditions described, it will be seen that the brake acts satisfactorily, the pressure below the diaphragm I being secured by means of a spring, by the regulating reservoir or by the auxiliary reservoir as preferred. In the two latter cases one may, if desired, make use of a valve of any suitable kindwhile with a spring it is necessary to employ a valve as specified above.

Instead of the diaphragms being arranged as in Fig. 7, they may be arranged as shown in Fig. 9 which, in order to sim )lify the matter, is in the form of a longitu inal diagrammatic section perpendicular to the plane passing through the axes of the valves and the junction pipes. The upper chamber communicates with the train pipe; A with the brake cylinder, P with the atmosphere and 0* with the regulating reservoir or the auxiliary reservoir under the same condi tions as above. These are simply a few details of construction presenting no difficulty to be dealt with in order to establish communication between the two chambers. B always communicates through a pipe and a non-return valve with the auxiliary reser therewith.

pipe runs directly to-the open air. As in the previously described apparatus, the upper diaphragm,may have a larger surface than the lower. This same remark also applies to the brake apparatus, of the differential and vacuum types hereafter described the object always being to efiect a rapid final releasing of the brake. vThis purpose may be effected with equal diaphragms that is to say diaphragms havin the same action under equal pressures, and with the addition of a spring action in the desired sense.

The foregomg explanations show that with the devices described a braking and release action capable of being moderated can be obtained. Moreover they are automatic regulators, that is to say that the pressure produced is maintained automatically. Thus a fixed pressure in the train pipe results from a certain determined pressure of the handle of the driversvalve. If there be some leakages in the train pipe tending to diminish the pressure produced this pressure is maintained at the fixed level by successive and suitable feeding. It will also be observed that the drivers valve enables a uniform maximum pressure to be maintained in the train pipe provided that the pressure in the principal reservoir be always above this maximum pressure. Under these circumstances, the pressure of the principal reservoir may vary within rather considerable limits without inconvenience. The drivers valve acts as a controllable expansion valve. Finally in making use of a regulating reservoir or of an adjustable spring of equivalent action for the distributer, it will be seen that the pressure of the air admitted into the brake cylinder that is to say the braking action only depends on the reduction effected in the train pipe and consequently is independent of the extent to which the brake blocks are worn.

The capacity of the auxiliary reservoir and the maximum pressure at which it is fed are calculated in such a manner that for the maximum reduction of the train pipe the pressure of the auxiliary reservoir is greater than that allowed in the brake cylinder. In a word the arrangement is such that there may always be excess pressure in the auxiliary reservoir. The object of this mechanism is that, if the operator turns hishandle to a determined osltion, there is admitted to all Y the brake-cy inders a pressure ap ropriate to the conditions mentioned. It is, owever, to be borne in mind that I employ concurrently with this arrangement a series of constituent parts which do not present any difliculty of construction, such as principal and auxihary reservoirs, compressors, pressure regulators for the compressors, drivers valves for the reservoirs, cocks for partial or entire shutting off of the operators valve or of the distributer, valves for the pipe-system, brake-cylinder, exhaust-valve to evacuate the latter and the auxiliary reservoir, piping, drivers connections, elastic couplings, etc.; all constitu- I ent arts are sufiiciently simple so that they nee not be specified here and the arrangement of which is known. On the other hand already described we will consider Fig. 10

which is a section through the perpendicular axis to the plane containing the axes of the valves E and F under the same conditions as in Fig. 9. The chamber B communicates with thetrain pipe, the chamber P with the atmosphere, the chamber A with the brake cylinder, the chamber C with the regulating reservoir or the auxiliary reservoir according to the circumstances, or there is a simple spring below the diaphragm I. It will be seen that the rod H is pressed with suiiicient force upward; it actuates the valve m by means of the lever Z that turns around a fixed point 0 The valve 9?. acts as a simple nonreturn valve. The action is as follows: If at the moment when the brakes are applied, a slight reduction be efi'ected, the action which affects the rod H and is the resultant of pfessures on the diaphragms raises the valve E before the stop d touches the lever Z. At this moment, the movement of the rod is arrested in consequence of the suitable tension imparted to the spring 1' or of the tension of a spring acting directly on the lever Z. The air admitted into the brake cylinder reestablishes equilibrium so that the action which tended to raise the rod H ceases, a further moderate reduction in the train pipe causes a further increase of pressure in the brake cylinder. In this way the pressure desired in the brake cylinder may be obtained without actuating the valve m provided that the reduction in the train pipe be produced gradually and without any sudden action. On

, the contrary if a sudden reduction be eltected the rod II is moved rapidly upward, and

then the resistance offered by the spring r or by that which acts on the lever isovercome and the air in the train pipe enters the brake cylinder, through the valves m and u at a moment when it is hardly fed by the auxiliary reservoir. The consequence of this is tin-accelerated reduction in the train pipe,

a reduction which being produced on each carriage will be so to speak instantaneous.

If the driver of the engine or the person who causes the stoppage contrives to exhaust the train pipe so that the pressure of this falls at any moment below that of the brake cylinder, the valve n prevents any return of air from the brake into the train pipe.

It is clear that instead of exhausting the train pipe through the valve m into the brake cylinder it may be exhausted into the open air through the same valve. The valve a. is no longer used, the valve m discharging directly into the atmosphere. Thus the reduction may be slightly more sudden. Either the one or the other arrangement is employed as preferred.

All these distributer arrangements may be applied to vacuum brakes, but the direction of the valves must be reversed. The valve E is arranged like the valve F and vice versa the non-return valves likewise are inverted. Moreover, in case a compression spring be employed it is placed in the chamber B in such a manner that it pushes the rod H upward. Rapid action may also be employed. In this case, the valves m and n are inverted and the lever Z inversely arranged. i

For actuating a differential brake the apparatus mustbe arranged as in Fig. 1.1. The differential brake is a brake in which the air compressed during the taking off of the brake, acts on the two faces of the brake cylinder piston. ervoir acts on the back. On the other hand through the medium of the distributerthe air of this same reservoir acts on the front face of the piston (the front being the direction in which the piston moves for the purpose of putting on the brake). \Vhen a reduction is caused in the train pipe, all communication between the chamber A and the auxiliary reservoir is shut off, and the air in the chamber A v which communicates with the brake cylinder is more or less completely exhausted according to the extent to which the brake is to be applied and which 0 depends on the difference of pressure on the two faces of the piston. The chamber S is in communication with the train-pipe and feeds the auxiliary reservoir by means of the valve 6 and the regulating reservoir through the valve b The valve 1) may The air of the auxiliary resbe dispensed with and the chamber T communicate directly with the auxiliary'reservoir which enables the regulating reservoir to be dispensed with. The action of the air of the chamber T may be repla ed by the action of a controllable spring. When air is let into the train-pipe, the valve E is actuated, which conveys the air from the auxiliary reservoir on to the front face of the piston. When a reduction is caused the front part of the brake cylinder is partly emptied through the valve F 6 a brake action which can be moderated is produced as desired. and taking otf the brake can be moderated. The rapid action arrangement may also easily be applied to this apparatus. It is clear that under the circumstances the discharging of the air from the train ipe into the cylinder cannot be thought 0 but the air from the train-pipe is discharged into the atmosphere. The arran ement of the chamber 13, Fig. 10, thus app ies completely but the valve "m, discharges directly into the open air and there is no longer any valve n.

In motor vehicles or vehicles provided with a principal reservoir the auxiliary reservoir may be dispensed with and the cylinder be fed with air from this principal reservoir through the medium of this distributer.

It will be observed it would not be possible really to consider the adoption of a distributer with a controllable spring J analogous to the ease illustrated in Fig. t except with a controllable valve. WVith a three way valve of the Westinghouse or other type the working would be impossible.

It will be observed that in Fig. 3 the bent lever U has a handle. The object of this handle is to enable a supplementary tension of the spring J to be effected, the consequence of which is a momentary increase of pressure in the train pipe, for the purpose of insuring the release of the brake.

The valves are supposed to have surfaces sutliciently small in relation to the surfaces of the diaphragms not to impede the general action.

The description furnished does not include any details of construction such as the details relating to the arrangement of the chambers. It should be understood in fact that .these apparatus may be constructed with all the alterations and modifications in construction suitable to the more general arrangements described, and it may also be observed that the diaphragms may be replaced by pistons. This obviously in no Way alters the general action. It is possible in fact if desired with a single slide valve controlled by the rod H by means of suitable communications, to realize the purpose fulfilled by the collection of supply, exhaust and non-return valves.

Ilere again the action of putting on What I claim is 1. In an apparatus of the character described the combination with a chamber in which the desired pressure is created, two valves one of which opens from said chamber toward the source of pressure, and the other from the atmosphere toward that chamber, levers connecting said valves, diaphragms arranged in said chamber as described and having surfaces of unequal area, an elastic device adapted to have its tension regulated and adapted to act upon said diaphragms as set forth.

2. In an apparatus of the character described, the combination with a chamber,

of valves E, F, arranged as described, th

diaphragms I I", the pivoted levers (1r adapted to engage with said valves, a movable rod H adapted to engage said levers,

and a spring J arranged to exert its tension upon the diaphragms.

3. In an apparatus of the character described, the combination with a chamber, of valves E, F, arranged as described, the diaphragms I,I, the pivoted levers G adapted to engage with said valves, a movable rod H ada ted to engage said levers, and a spring J arranged to exert its tension upon the diaphragms, a lever Vengaging the rod H, and a spring arranged to act upon the lever V.

In testimony whereof I afiix my signature in presence of two witnesses. F

JOSEPH EDOUARD ALEXANDRE MICHEL.

Witnesses;

H. C. Com, VICTOR MATRAU. 

